What happens if you start digging straight down to the center of the earth? How far have humans been able to dig down ? Why should we care what is inside of the earth ?

the deepest hole humans have ever dug was about 7.5 miles deep which was in Murmansk, Russia

Explanation:

well it is not easy to dig down to the center of the earth but according to scientist the time when you jump down to the earth until you reach the other side is 42 min by which you will reach the center of the earth after 21 min by which you will go down in a lot of speed

answer called a epicycle;